aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/i2c/i2c-core-acpi.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2018-08-20i2c: core: ACPI: Make acpi_gsb_i2c_read_bytes() check i2c_transfer return valueHans de Goede1-3/+5
Currently acpi_gsb_i2c_read_bytes() directly returns i2c_transfer's return value. i2c_transfer returns a value < 0 on error and 2 (for 2 successfully executed transfers) on success. But the ACPI code expects 0 on success, so currently acpi_gsb_i2c_read_bytes()'s caller does: if (status > 0) status = 0; This commit makes acpi_gsb_i2c_read_bytes() return a value which can be directly consumed by the ACPI code, mirroring acpi_gsb_i2c_write_bytes(), this commit also makes acpi_gsb_i2c_read_bytes() explitcly check that i2c_transfer returns 2, rather then accepting any value > 0. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-20i2c: core: ACPI: Properly set status byte to 0 for multi-byte writesHans de Goede1-3/+8
acpi_gsb_i2c_write_bytes() returns i2c_transfer()'s return value, which is the number of transfers executed on success, so 1. The ACPI code expects us to store 0 in gsb->status for success, not 1. Specifically this breaks the following code in the Thinkpad 8 DSDT: ECWR = I2CW = ECWR /* \_SB_.I2C1.BAT0.ECWR */ If ((ECST == Zero)) { ECRD = I2CR /* \_SB_.I2C1.I2CR */ } Before this commit we set ECST to 1, causing the read to never happen breaking battery monitoring on the Thinkpad 8. This commit makes acpi_gsb_i2c_write_bytes() return 0 when i2c_transfer() returns 1, so the single write transfer completed successfully, and makes it return -EIO on for other (unexpected) return values >= 0. Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: core: ACPI: Log device not acking errors at dbg loglevelHans de Goede1-4/+10
Unfortunately some DSDTs issue bogus i2c reads to non existing devices resulting in -EREMOTEIO errors because the non existing device of course does not ack. This happens e.g. from the The Asus T100TA's _BIX method, the DSDT on the T100TA defines 2 resources on the I2C1 bus: Name (EHID, ResourceTemplate () { I2cSerialBusV2 (0x005B, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , Exclusive, ) }) OperationRegion (EHOR, GenericSerialBus, Zero, 0x0100) Field (EHOR, BufferAcc, NoLock, Preserve) { Connection (EHID), Offset (0x01), AccessAs (BufferAcc, AttribBytes (0x10)), ABCD, 8 } Name (UMPC, ResourceTemplate () { I2cSerialBusV2 (0x0066, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , Exclusive, ) }) The _BIX method does a single read (on each BIX() call) from the EHID device through the ABCD Field, only to completely ignore the result. This read always fails as there is no i2c client at address 0x5b. The _BIX method also does several reads from the UMPC device and actually uses the results of those to provide battery information. IIRC I've also seen some DSTDs which do an i2c read to detect if a device is present, also leading to false positive errors being logged. Esp. the _BIX use is problematic as the _BIX method gets called periodically to monitor battery status. This commit stops the logs from filling up with errors like these: [ 57.327858] i2c i2c-0: i2c read 16 bytes from client@0x5b starting at reg 0x1 failed, error: -121 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30i2c: core: ACPI: Improve OpRegion read errorsHans de Goede1-1/+2
When we get an error doing an ACPI SerialBus I2C OpRegion read log some useful details, like the client address and which register is being read. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-31i2c: core: Allow empty id_table in ACPI case as wellAndy Shevchenko1-4/+15
For now empty ID table is not allowed with ACPI and prevents driver to be probed. Add a check to allow empty ID table. This introduces a helper i2c_acpi_match_device(). Note, we rename some static function in i2c-core-acpi.c to distinguish with public API. Fixes: da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed devices") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Rajmohan Mani <rajmohan.mani@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> [wsa: needed to get some drivers probed again] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-04i2c: acpi: Do not create i2c-clients for LNXVIDEO ACPI devicesHans de Goede1-0/+12
ACPI video devices get tagged by the kernel with the custom LNXVIDEO HID so that normal pnp-id matching can be used and are handled by the acpi-video driver. Sometimes the ACPI nodes describing these contain a SERIAL_TYPE_I2C ACPI resource. Before this commit the presence of this resource would cause the i2c-core to create a /sys/bus/i2c/devices/i2c-LNXVIDEO:00 device for this with a modalias of: "i2c:LNXVIDEO:00". There is no i2c driver for this custom HID, the acpi-video driver binds directly to the ACPI device /sys/bus/acpi/devices/LNXVIDEO\:00 which has a modalias of "acpi:LNXVIDEO:" . Not only is the creation of an i2c-client for this undesirable, it is actually causing problems. This weird pseudo-resource claims an i2c speed of 100KHz and typically points to the i2c bus which is used by the touchscreen controller. Some touchscreen controllers only work properly at 400KHz, at 100KHz they cause errors like these: i2c_designware 80860F41:03: i2c_dw_handle_tx_abort: lost arbitration i2c_designware 80860F41:03: i2c_dw_handle_tx_abort: lost arbitration i2c_designware 80860F41:03: i2c_dw_handle_tx_abort: lost arbitration i2c_designware 80860F41:03: i2c_dw_handle_tx_abort: lost arbitration silead_ts i2c-MSSL1680:00: Registers clear error -11 This commit makes the i2c-core ignore LNXVIDEO compatible ACPI devices which has 2 positive results: 1) The bogus i2c-client for these is no longer created. 2) i2c_acpi_lookup_speed now ignores the 100KHz speed from the pseudo i2c-resouce and properly returns 400KHz as speed for the touchscreen i2c bus, fixing the touchscreen not working on various devies. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out ACPI support into separate fileWolfram Sang1-0/+653
Removes some ifdeffery. Also add the new file to the relevant MAINTAINERS section. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>